Appearing on CNN's \"State of the Union,\" Zimmer said she was told by a member of Christie's administration that Sandy relief funds hinged on her support for a real estate development project and that the directive was coming directly from Christie.

\"She said that to me -- is that this is a direct message from the Governor,\" Zimmer said, referring to Lt. Gov. Kim Guadagno, who Zimmer said approached her in a parking lot in May to deliver the message.

Later in the day, she released a statement saying that she had met with the U.S. Attorney's Office for several hours at its request and provided the office with her journal and other documents.

\"As they pursue this investigation, I will provide any requested information and testify under oath about the facts of what happened when the Lieutenant Governor came to Hoboken and told me that Sandy aid would be contingent on moving forward with a private development project,\" she said.

Zimmer said the Christie administration wanted her to approve a project by The Rockefeller Group, a real estate developer with ties to Christie's administration.

When asked by CNN to respond to Zimmer's accusation that Christie had a direct hand in the threat, Christie spokesman Colin Reed refused to address it and instead referred to a previous statement, which said Zimmer's allegations that relief funds were withheld is based on partisan politics.

The allegations come as other controversies revolve around Christie's administration. In one, evidence mounts showing that Christie aides were involved in tying up traffic in a town at the foot of the George Washington Bridge in what may have been an act of political retribution against another mayor. In another, the Christie administration hired a firm for post-Sandy tourism ads that cost nearly twice as much as the next highest proposal.

This is the first time Christie has been directly connected to the controversy.

Christie administration pushes back

In his statement to CNN on Saturday, Reed blasted Zimmer's claim that the funds were based on the real estate project. He said her accusations are false, adding, \"It's very clear partisan politics are at play here as Democratic mayors with a political ax to grind come out of the woodwork and try to get their faces on television.\"

Reed went on to attack the cable news channel that first broke the news Saturday. \"MSNBC is a partisan network that has been openly hostile to Governor Christie and almost gleeful in their efforts attacking him,\" Reed said.

MSNBC said its story is based on an interview with Zimmer \"and e-mails and personal notes she shared with MSNBC.\"

The Governor's spokesman also said the Mayor and Governor have had a \"productive relationship,\" noting an August tweet by Zimmer saying she's \"very glad Governor Christie has been our Gov.\"

Zimmer's comments Saturday and Sunday are a change from what she told CNN just last week, when she said that while she wondered whether Sandy aid funds were being withheld because she didn't endorse the governor's re-election, she concluded that \"I don't think that's the case.\"

\"I don't think it was retaliation and I don't have any reason to think it's retaliation, but I'm not satisfied with the amount of money I've gotten so far,\" Zimmer told CNN last week, not mentioning her concerns about the redevelopment project.

But Sunday morning, Zimmer told CNN's Crowley that she didn't speak out before because she didn't think anyone would believe her, adding that she is now \"offering to testify under oath.\"

Zimmer admitted to supporting Christie in the past, saying she is not a part of \"the Democratic machine.\" But the information around the George Washington Bridge scandal -- involving lane closures at the entrance to the busy bridge, apparently for political retaliation -- prompted her to speak. She said she sees parallels between her story and the bridge controversy: \"The Christie administration using their authority to try and get something.\"

Zimmer said Guadagno appeared to feel guilty for delivering the message.

\"I believe if and when she is asked to testify under oath, the truth will come out, because I believe she will be truthful and she will tell the truth,\" Zimmer told Crowley.

Zimmer also said she is speaking because she wants Hoboken to receive an appropriate level of funds in the second round of recovery dollars about to be released.

Sandy recovery funds

After Sandy, Hoboken was 80% underwater. Zimmer told CNN last week that Hoboken received only about $300,000 of the roughly $100 million in state funds the city requested for flood prevention.

Reed, Christie's spokesman, told CNN that Zimmer asked for $100 million from a roughly $300 million pot of money for which there was $14 billion worth of requests.

Since that request, Reed said, Hoboken has been approved for nearly $70 million in aid. The city has also been identified as a pilot community for a federal program to prevent flooding, one of only four such projects in New Jersey.

Zimmer, however, had a different account of allocated funds. She said the $70 million given to Hoboken was through flood insurance and other mechanisms that did not need approval from the state. She received only $300,000 in Christie-approved funds, she said.

CNN received images of journal entries from the Mayor's office that Zimmer told CNN she wrote at the time.

In one, Zimmer writes that the conversation with Guadagno left her upset and shattered the image she had of Christie.

\"I thought he was honest, I thought he was moral -- I thought he was something very different. This week I found out he's cut from the same corrupt cloth that I have been fighting for the last four years. I am so disappointed -- it literally brings tears to my eyes,\" the journal entry says.

Zimmer also wrote that Guadagno told her she needs \"to move forward with the Rockefeller project. It is very important to the Gov.\"

Reed, asked by CNN about Zimmer's comments on Guadagno, said, \"Mayor Zimmer's characterization of her conversation in Hoboken is categorically false.\"

Three days after the purported Guadagno comments, state Community Affairs Commissioner Richard Constable was on a panel with Zimmer, discussing Sandy relief.

Zimmer told MSNBC that Constable leaned over and told her, \"If you move (the redevelopment project) forward, the money would start flowing to you.\"

In a statement to CNN, Constable spokeswoman Lisa Ryan said, \"Mayor Zimmer's allegations that on May 16, 2013, in front a live auditorium audience Commissioner Constable conditioned Hoboken's receipt of Sandy aid on her moving forward with a development project is categorically false.\"

Debate about redevelopment

Zimmer's claims center around a property owned by The Rockefeller Group, which had its plan for \"redevelopment\" of a three-block area of Hoboken rejected by the city's planning board. Instead, the panel voted to classify the area owned by the company as available for \"rehabilitation.\" The \"redevelopment\" label was sought because its tax incentives offered a much more lucrative deal for the development company.

Aides and advisers to Christie have ties to Wolff & Samson, the law firm representing The Rockefeller Group.

The Hoboken Planning Board rejected the \"redevelopment\" plan three days before Zimmer was allegedly first approached by Guadagno.

Zimmer provided MSNBC with a 2012 e-mail from Wolff & Samson's Lori Grifa -- previously commissioner of the New Jersey Department of Community Affairs -- to Hoboken's lawyer that shows her lobbying on behalf of the project: \"Our client, The Rockefeller Group, has specifically asked us to speak with you regarding its property in Hoboken.\"

Grifa is not the only connection between the Christie administration and The Rockefeller Group. The Samson in Wolff & Samson is David Samson, chairman of the Port Authority, who was appointed by Christie. Samson was recently served with a subpoena in the George Washington Bridge case by an investigative committee seeking relevant documents.

The Rockefeller Group told CNN, \"We have no knowledge of any information pertaining to this allegation. If it turns out to be true, it would be deplorable.\"

The law firm, in a statement, denied Zimmer's allegations and said it did nothing wrong: \"The firm's and Ms. Grifa's conduct in the representation of our client was appropriate in all respects. Further, Ms. Grifa notes that while DCA Commissioner, she never met with Mayor Zimmer or The Rockefeller Group to discuss the Hoboken project.\"

Zimmer told MSNBC that she couldn't agree to The Rockefeller Group proposal because \"there are fundamental problems with the site in northern Hoboken, including traffic and flooding issues, that would be magnified if the plan were to go forward.

A spokesperson for The Rockefeller Group told CNN that it still hopes to develop the site under the designation of \"rehabilitation,\" but that this is \"contingent on the plan the city comes up with.\"

Another investigation?

As word of the allegations spread Saturday, the chairman of the investigative committee tasked with looking into the George Washington Bridge scandal weighed in.

Assemblyman John Wisniewski, D-Middlesex, told CNN: \"This certainly has attracted our attention. We need to obtain all relevant facts, confer with our special counsel and determine the committee's best course of action.\"